TY - GEN
T1 - An enhancement to speed estimation using single loop detectors
AU - Lin, Wei Hua
AU - Dahlgren, J.
AU - Huo, Hong
N1 - Publisher Copyright:
© 2003 IEEE.
PY - 2003
Y1 - 2003
N2 - Speed estimation plays an important role in many components in intelligent transportation systems (ITS). In practice, traffic data from single loop detectors are one of the dominant data sources. Speed estimation from single loop detectors is mainly based on occupancy data, a conversion factor from occupancy to density (which is potentially related to the vehicle length), and the assumed relationship between flow, speed, and density. This paper investigates the discrepancy between the speed estimated with single loops and the speed estimated with double loops. It was found that the discrepancy between the two is mainly caused by the high variance in vehicle pace, which, especially under congested traffic, is often accompanied with the high skewness. Accuracy can be improved by computing occupancy in a different way, using the median vehicle passage time over the detector as opposed to the mean vehicle passage time often used in the conventional method. The performance of the enhanced speed estimation method is very promising. The use of the median vehicle passage time reduces the skewness of pace data.
AB - Speed estimation plays an important role in many components in intelligent transportation systems (ITS). In practice, traffic data from single loop detectors are one of the dominant data sources. Speed estimation from single loop detectors is mainly based on occupancy data, a conversion factor from occupancy to density (which is potentially related to the vehicle length), and the assumed relationship between flow, speed, and density. This paper investigates the discrepancy between the speed estimated with single loops and the speed estimated with double loops. It was found that the discrepancy between the two is mainly caused by the high variance in vehicle pace, which, especially under congested traffic, is often accompanied with the high skewness. Accuracy can be improved by computing occupancy in a different way, using the median vehicle passage time over the detector as opposed to the mean vehicle passage time often used in the conventional method. The performance of the enhanced speed estimation method is very promising. The use of the median vehicle passage time reduces the skewness of pace data.
KW - Traffic sensors
KW - traffic control
KW - traffic flow theory
KW - traffic management systems
KW - traveler information systems
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U2 - 10.1109/ITSC.2003.1251988
DO - 10.1109/ITSC.2003.1251988
M3 - Conference contribution
AN - SCOPUS:33746348530
T3 - IEEE Conference on Intelligent Transportation Systems, Proceedings, ITSC
SP - 417
EP - 422
BT - Proceedings of the 2003 IEEE International Conference on Intelligent Transportation Systems, ITSC 2003
PB - Institute of Electrical and Electronics Engineers Inc.
T2 - 2003 IEEE International Conference on Intelligent Transportation Systems, ITSC 2003
Y2 - 12 October 2003 through 15 October 2003
ER -